Coffee is in an insulated cup 0.5 cm thick in the shape of a cube 10 cm on a side. The cup has a very small opening (its area is much smaller than the area of a square wall) through which coffee can be drunk. The temperature of the coffee is 95oC and the surrounding temperature is 21oC. Find the ratio of the heat loss due to conduction to the heat loss due to the radiation. Assume the emissivity of 1.0 and the thermal conductivity of cup of 2 x 10-4 cal/cm.s.°C. 1 x 10-3.